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Species Oryzaephilus mercator - Merchant Grain Beetle

Oryzaephilus - grain beetle - Oryzaephilus mercator grain beetle larva - Oryzaephilus mercator Unknown beetle - Oryzaephilus mercator Oryzaephilus surinamensis? - Oryzaephilus mercator Unknown Beetle - Oryzaephilus mercator Merchant Grain Beetle - Oryzaephilus mercator Indoor beetle - Oryzaephilus mercator Very Small Beetle - Oryzaephilus mercator
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Coleoptera (Beetles)
Suborder Polyphaga
No Taxon (Series Cucujiformia)
Superfamily Cucujoidea
No Taxon (Cucujid series)
Family Silvanidae (Silvanid Flat Bark Beetles)
Subfamily Silvaninae
Genus Oryzaephilus
Species mercator (Merchant Grain Beetle)
Explanation of Names
Oryzaephilus mercator (Fauvel 1889)

The two Oryazephilus common in the US can be distinguished by a projection or bump just behind the eye. In O. surinamensis, this area is broad and blunt, and in mercator it is narrow and more protruding.

Left: O. surinamensis, right: O. mercator.
cosmopolitan; adventive in NA - Map (3)(4), of tropical origin(5)
a common household pest(3), in Canada found more frequently in apartments and other multiple dwellings than in houses(1)
Adults and larvae feed primarily on cereal products, particularly oatmeal, bran, shelled sunflower seeds, rolled oats, and brown rice(3); usually associated with oilseeds and less with cereal grains and in most regions damages processed cereals, especially those with high oil content; also feeds on seed-borne fungi(6)
Works Cited
1.Beetles associated with stored products in Canada: An identification guide
Bousquet Y. 1990. Research Branch Agriculture Canada, Publication 1837.
2.Insect and Mite Pests in Food, an Illustrated Key
J. Richard Gorham, editor. 1991. United States Department of Agriculture Handbook 655.
3.The flat bark beetles (Coleoptera, Silvanidae, Cucujidae, Laemophloeidae) of Atlantic Canada
C.G. Majka. 2008. ZooKeys 2: 221-238.
4.Global Biodiversity Information Facility (GBIF)
5.Coleoptera families other than Cerambycidae, Curculionidae sensu lato, Chrysomelidae sensu lato and Coccinelidae -- Chapter 8.5
Denux O., Zagatti P. 2010. BioRisk 4: 315–406.
6.Handbook of urban insects and arachnids: A handbook of urban entomology
Robinson W.H. 2005. Cambridge University Press.